*{padding: 0;margin: 0;}  /* 先重置一下html，消除HTML标签默认的内外边距 */
body{margin: 0 auto;background: url("../images/a1.jpg");  background-repeat: no-repeat;
    background-size:100%;background-attachment: fixed;
}

/* 清除浮动 */
/*.header{opacity: 0.5;filter:alpha(opacity=50);}*/
.biaoti{margin-left:20px}
.biaoti1{width: 1500px;}
.div1{  padding-top:30px;width:1200px;height:1200px;background-color: #FFFFFF;margin-left: 180px;background: rgba(255,255,255,.5)}/*0是灰色透明背景*/
.div3{margin-top: 10px;width:750px;height:800px;float: left;background-color: #FFFFFF;background: rgba(255,255,255,.6);}
.img1{float: left;margin-left: 20px;margin-top: 30px;}
.img2{margin-top: 30px;margin-left: 10px;}
.img3{margin-top: 10px;margin-left: 10px;}
.div4{margin-top: 10px; margin-left: 770px; width: 400px;height: 380px;background-color: #FFFFFF;background: rgba(255,255,255,.6)}
.div5{margin-top: 10px; margin-left:770px;width: 400px;height: 410px;background-color: #FFFFFF;background: rgba(255,255,255,.6)}
h1{font-size: 24px;padding-top: 30px;}
nav{margin-left: 100px}
a{text-decoration-line: none;}   /* 去掉默认a标签的下划线 */
ul,li{list-style: none;}
nav .A-ul>li{float: left;width:13%;text-align: center;background:#6E6E6E;padding: 10px 0;font-size: 16px;position: relative;}
nav .A-ul>li a{color:#FFFFFF;}
nav .A-ul>li:hover{background:#4D4D4D;}   /* 设置鼠标滑过后的样式 */
nav .B-ul{display: none;position: absolute;
    left: 0;
    width: 100%;
    top: 43px;
    text-align: center;
    background: #4D4D4D;}  /* 先使二级菜单的内容隐藏 */
nav .A-ul>li:hover .B-ul{display: block;}   /* 鼠标滑过一级菜单后的显示二级菜单 */
nav li{  border-bottom:1px solid #383838;/*二级菜单下划线*/  padding: 5px;/*二级菜单间距*/  }
nav li a:hover{  color: #F00408;/*文字变色*/  }

.button1{width:30%;height:100px;text-align: center;background:#68838B;margin-left: 150px;color:#FFFFFF}
.caret {
    display: inline-block;
    width: 0;
    height: 0;
    margin-left: 2px;
    vertical-align: middle;
    border-top: 4px solid;
    border-right: 4px solid transparent;
    border-left: 4px solid transparent;
    color:#FFFFFF;
}/*倒三角*/

.div2{width: 900px;height: 150px;background: #FFFFFF;background: rgba(255,255,255,.6);margin-top: 50px;margin-left:15px;}
.mp3{margin-top: 250px;margin-left:120px;}
.footer{background-color: #FFFFFF;background: rgba(255,255,255,.4);margin-top: 15px;}